Ring-shaped element of prismatic section for improving the luminosity of electric lamps



RING-SHAPED ELEMENT OF PRISMATIC SECTION FOR y 1938- A. G-UNSBOURG2,123,942

IMPROVING THE LUMINOSITY OF ELECTRIC LAMPS Filed May 26, 1936 PatentedJuly 19, 1938 UNITED STATES PATENT OFFIE Rl'NG- SHAPED ELEDIENT OFPRISMATIC Arcadius Gunsbourg, Brussels, Belgium Application May 26, InBelgium 2 Claims.

The present invention relates to a ring-shaped reflector element forimproving the luminosity of electric lamps, by concentrating the lightrays in a determined direction.

The invention has for its object to construct such ring-shaped elementpreferably in one piece and adapted to be directly supported by the bulbof an electric lamp.

Annular reflectors have been used with electric lamp bulbs, but theypresented the drawback of requiring mechanical means for fixing the sameto the lamps, and this constitutes a constructional complication. It hasfurthermore been proposed to use hollow cone-shaped reflectors melted onthe lamp bulb or loosely put over it so that the hollow cone alwaysextends below the source of light.

The present invention has for its object an annular reflector to beloosely mounted on an electric lamp bulb, formed of transparent ortranslucent material and having inner and outer coaxial andfrustro-conical surfaces of revolution which diverge downwardly, thereflector being provided at its upper end with an integral collar to fitover the bulb.

The article will be made of glass or any other transparent ortranslucent material and this material may be colored. Between thesupport ing collar and the lamp bulb may be inserted adjusting elementshaving a resilient character or adapted to compensate for the volumetricmodifications or expansions of the materials in contact, said elementsbeing, for instance made of a metal foil, asbestos or like substance.Such insert elements may obviously be made as a reflecting surface, soas to constitute an auxiliary reflector capable of also directing thelight rays in a convenient direction.

The inner or outer surface of the collar may be metallized, silvered,gilded or the like. The outer surface of the body may be coated with areflecting material.

The invention will be described with reference to the accompanyingdrawing, in which two forms of embodiment are illustrated.

Fig. 1 is an axial section of the simplest form supported by a lampbulb.

Fig. 2 is an axial section of a modified form of embodiment.

In Fig. 1, I designates the reflector with its downwardly diverginginner and outer coaxial surfaces of revolution, and I3 the collar sur-1936, Serial No. 81,838 April 22, 1936 mounting the reflector. The axialsection of the prismatic body is selected so as to produce the mostefficient concentration of the light rays.

For the purpose of increasing the concentration of the light rays andreducing the diffusion of reflected rays, it is useful to multiply thereflection effect. Therefore, the outer surface of the circularreflector will be provided with a number of coaxially disposed annularfacets. The number of annular facets is variable as are also theirdimensions.

' Fig. 2 illustrates. diagrammatically such form of embodiment.

The outer surface of the reflector is composed of the coaxialfrustro-conical surfaces 3, 4, 5, while the inner surface isfrustro-conoidal. The arrangement will be preferably so that the rays 6,'l, and 8, emitted for instance from the luminous source 9 of the lamp2, produce reflected rays I0, II, l2, substantially parallel to eachother.

Obviously, numerous constructional modifications may be introduced inthe forms of embodiment illustrated. As stated herebefore, the inner orouter face of the suspending collar may be formed as a reflector; theouter face of the reflector body may also be coated so as to form areflector; portions of the element may be frosted; the material,preferably glass, may have different degrees of transparency orcoloration, so as to present an ornamental character. For varying thecoloration, difierent compositions may be used, such as for instance theusual mixture for producing glass to which is added cobalt oxide,pigments, mercury salts, lead oxides and the like.

I claim:

1. An annular reflector to be loosely mounted on an electric lamp bulb,formed of lightpermeable material and having inner and outer coaxial andfrustro-conical surfaces of revolution which diverge downwardly, thereflector being provided at its upper end with an integral collar to fitover the bulb.

2. An annular reflector to be loosely mounted on an electric lamp bulb,formed of transparent material and having inner and outer coaxial andfrustro-conical surfaces of revolution which diverge downwardly, theouter surface being composed of a plurality of coaxial frustro-conicalsurfaces and the inner surface being frustroconoidal, the reflectorbeing provided at its upper end with an integral collar to fit over thebulb.

' ARCADIUS GUNSBOURG.

